Light-Emitting Module and Lighting Apparatus

ABSTRACT

A light-emitting module may be configured to have improved light emission efficiency and light distribution characteristics. A light-emitting module may include a substrate having a front surface side as a component mounting surface and a rear surface side as a flat heat dissipating surface, a plurality of light-emitting elements arranged in a manner protruding at a central portion of the component mounting surface of the substrate. The light-emitting elements may radiate light at least in an upper surface direction and in a direction along the component mounting surface. The module may further include one or more lighting circuit components electrically connected to the light emitting elements by a wiring pattern arranged on the substrate and which is arranged closer to the peripheral edge side of the substrate than the light emitting elements on the component mounting surface of the substrate, and a connector for power supply connection.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 12/867,134entitled “LIGHT-EMITTING MODULE AND LIGHTING APPARATUS” and was filed onSep. 23, 2010, which is a national stage entry of PCT Application No.PCT/JP2009/052382, filed on Feb. 13, 2009, and claims priority toJapanese Application No. 2008-118292, filed Apr. 30, 2008 and JapaneseApplication No. 2008-033673 filed Feb. 14, 2008. The contents of theabove noted applications are incorporated by reference herein in theirentirety.

TECHNICAL FIELD

Aspects of the present disclosure relate to a light-emitting module inwhich a light-emitting element such as LED is arranged. In someexamples, aspects relate to a lighting apparatus provided with thelight-emitting module.

BACKGROUND

In some known arrangements, LED chips and circuit components aredisposed on a surface of the LED module in a mixed manner. Therefore,these known arrangements fail to disclose any technical idea forperforming excellent distribution of light radiated from the LED chip,and moreover, there is no description of using a rear surface of the LEDmodule as a heat dissipating surface. Furthermore, in some knownconfigurations of a power feeding terminal and a holding member, thedisclosed LED module has a specific structure for attachment andconnection, which requires a specified adaptor, thus lackingversatility.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view illustrating a first embodiment of alight-emitting module according to the present invention.

FIG. 2 is a partial side view, in an enlarged scale, illustrating thelight-emitting module according to the present invention.

FIG. 3 is a circuit diagram of the light-emitting module according tothe present invention.

FIG. 4 is a schematic diagram illustrating a structure of a firstembodiment of a lighting apparatus according to the present invention.

FIG. 5 is a schematic diagram illustrating a structure of a secondembodiment of the lighting apparatus according to the present invention.

FIG. 6 is a schematic diagram illustrating a structure of a thirdembodiment of the lighting apparatus of the present invention.

FIG. 7 is a plan view illustrating a modification of the light-emittingmodule according to the first embodiment.

FIG. 8 is a plan view (8(a) and a side view 8(b)) illustrating thelight-emitting element (LED package) according to the first embodimentof the light-emitting module.

FIG. 9 is a graph showing a directional pattern of radiant light of thelight-emitting element.

FIG. 10 is a plan view illustrating an arrangement of the light-emittingelements.

FIG. 11 is a schematic view showing illuminance distribution on a floorsurface when the light-emitting module is lightened.

FIG. 12 is a graph representing luminance irregularity and lightemitting efficiency relative to the interval between the light-emittingelements.

FIG. 13 is an explanatory view illustrating an example of anotherapplication of the light-emitting element.

DETAILED DESCRIPTION

Aspects described herein relate to improving upon the abovecircumstances, and to provide a light-emitting module having excellentlight emission efficiency and excellent light distributioncharacteristics and also provide a lighting apparatus using thelight-emitting module.

A light-emitting module according to aspects described herein includes:a substrate having a front surface side constituted as a componentmounting surface and a rear surface side constituted as a heatdissipating surface flat in shape; a plurality of light-emittingelements mounted at a central portion of a component mounting surface ofthe substrate in a manner protruding therefrom and emitting light atleast in an upper surface direction and in a direction along thecomponent mounting surface; a lighting circuit component which iselectrically connected to the light emitting elements by a wiringpattern arranged on the substrate and which is arranged on a peripheraledge side of the substrate than the light emitting elements, on thecomponent mounting surface of the substrate; and a connector forconnecting with a power supply, which is arranged on the peripheral edgeside of the substrate than the light emitting elements, on the componentmounting surface of the substrate, and which is electrically connectedto the lighting circuit component.

In some examples, a light emitting module having wide applicable rangecan be provided with excellent light distribution characteristics andmade optimized. Moreover, heat dissipation effects can be promoted andthe wiring pattern on the substrate can be shortened and simplified,thus being effective.

Furthermore, in some arrangements, it may be desired that the pluralityof light-emitting elements are arranged at even intervals in rotationalsymmetry except at a central point of the central portion of thecomponent mounting surface of the substrate. According to thisarrangement, since the plurality of light emitting elements arearranged, it becomes possible to perform heat radiation in aconcentrated manner from a portion near the center point of thesubstrate toward the rear surface side thereof, thus realizingsubstantially even light distribution characteristics in the horizontaldirection.

Additionally or alternatively, it may be desired that when it issupposed that a minimum distance between light-emitting portions of theplurality of the light-emitting elements arranged is c, a width of thelight-emitting portion on a line of the minimum distance c is a, and aheight from the mounting surface of the substrate to an upper surface ofthe light-emitting portion is b, the light-emitting elements arearranged so as to satisfy a dimensional relationship of b<c<4a.According to this arrangement, the light-emitting module havingsuppressed luminance irregularity is obtainable, thus providingexcellent light emission efficiency.

A first embodiment of the present invention will be described below withreference to FIGS. 1 to 3. FIG. 1 is a plan view illustrating alight-emitting module, FIG. 2 is a partial enlarged side viewillustrating a light-emitting element, and FIG. 3 is a circuit diagramof the light-emitting module.

Referring to FIG. 1, a light-emitting module 1 includes a disc-shapedsubstrate 2, light-emitting elements 3 mounted on the substrate 2, alighting circuit components 4, and a connector 5 for power sourceconnection.

The substrate 2 is made of aluminum, which is formed into a disc plateshape, and having a thickness of about 1.5 mm and a diameter of about 70mm. In the substrate 2, a front surface side 2 a is used as a componentmounting surface, and a rear surface side 2 b is used as a flat-shapedheat dissipating surface. On the component mounting surface, eightlight-emitting elements 3 are mounted in a manner concentrated in thecentral portion of the component mounting surface in a pattern spacedwith a predetermined interval from each other. When the substrate 2 ismade of metal, it is preferred to use a material such as aluminum orcopper which is excellent in heat conductivity and heat dissipationcharacteristics. On the other hand, when an insulating material is usedfor the substrate 2, a synthetic resin material or a ceramic materialcontaining thermal conduction filler, which has relatively excellentheat dissipation characteristics and excellent durability, may beutilized. In the case of using the synthetic resin material, thesubstrate 2 may be formed of glass epoxy resin or the like. Further, theshape of the substrate 2 is not limited to circle and may be quadrangleor polygon.

The light-emitting elements 3 are a surface-mounted LED package and aremainly constituted of a main body 3 a formed of ceramic, an LED chipmounted on the main body and a translucent resin 3 b for mold use, suchas epoxy resin or silicon resin, which seals the LED chip (refer to FIG.2). A pair of lead terminals, not shown, connected to the LED chipprojects from the main body 3 a in a horizontal direction. In the LEDpackage, four LED chips are mounted, which are connected in seriesbetween electrodes of the package, and accordingly, since eight LEDpackages each having four LED chips are arranged, totally, thirty two(32) LED chips are arranged. Needless to say, an LED package may also beused in which a single LED chip is mounted.

The LED chip is a blue LED chip emitting blue light. The translucentresin 3 b for mold use contains a fluorescent material which absorbslight emitted by the LED chip and generates yellow light. The LED chipis molded on an upper surface of the main body 3 a so as to form a flatplate with a predetermined thickness. Accordingly, light from the LEDchip is irradiated from an upper surface and a side surface of thetranslucent resin 3 b of the LED package to the outside, and hence, thelight from the LED chip has a white-base luminescent color such as whitecolor or electric bulb color and has wide light distributioncharacteristics. That is, light is irradiated from the light-emittingelements 3 in a direction of the upper surface thereof and in adirection along the component mounting surface. Further, the LED packageis about 3.5 mm in breadth, 3.5 mm in width and 1.5 mm in height and hasa shape of a substantially rectangular solid.

An insulating layer is formed on a surface of the substrate 2, and onsuch insulating layer, a connection land connected to lead terminals ofthe surface-mounted components and a wiring pattern, not shown, areformed. In the central portion of the substrate 2 except at a centralpoint thereof, the light-emitting elements 3 are arranged at apredetermined interval (3 mm to 15 mm, preferably 5 mm to 10 mm) inrotational symmetry (in the present embodiment, being 45.degree.symmetry relative to the light emission center of the light-emittingelements 3) around the central point along a direction of the frontsurface of the substrate 2. Further, the lighting circuit components 4are arranged and mounted in an outer peripheral edge side of thesubstrate 2, and in this case, the lighting circuit components 4 arenever mounted between the light-emitting elements 3 and 3. The lightingcircuit components 4 are used for lighting control of the LED chip, andinclude a fuse F, a capacitor C, a rectifier REC, a constant voltagediode ZD, resistors R1 and R2, and a transistor Q. A connector 5 forconnecting with a power supply is similarly arranged in a positionaround the light-emitting elements 3. The connector 5 is arranged sothat a connection opening 5 a thereof faces the outer peripheral edge ofthe substrate 2 and is disposed close to the outer peripheral edge. Thisis for the purpose of facilitating the connection with a power line ofcommercial power supply. The lighting circuit components 4 and theconnector 5 are disposed closer to the outer peripheral edge side of thesubstrate 2 than the light-emitting elements 3, and arranged not in adispersed manner but in a relatively concentrated manner (in a regiondisposed approximately ⅓ from the outer circumference of the substrate2) to shorten the wiring pattern of the substrate 2. On the mountingsurface of the substrate 2, a white resist having a high reflectivity isprinted, and three screw through-holes 6 are formed on the mountingsurface to be mounted onto an apparatus or the like.

The light-emitting elements 3 protrude from the mounting surface of thesubstrate 2 in a direction of height, and radiate, as indicated by thearrow in FIG. 2, light in a radial pattern from a protruding portion ofthe translucent resin 3 b. Accordingly, not only the light LV radiatedin a direction perpendicular (upper surface direction) to the mountingsurface, but also the light LH radiated from the side surface of thetranslucent resin 3 b of the LED package along the component mountingsurface can be used.

Referring to the circuit diagram of FIG. 3, the capacitor C is connectedvia the fuse F across a commercial power supply AC. The full-waverectifier REC is connected across the capacitor C, and in the outputterminal of the full-wave rectifier REC, a series circuit of theresistor R1 and the constant voltage diode ZD, and a series circuit of aplurality of the LED chips LED, the NPN transistor Q and the resistor R2are connected in parallel. A base of the transistor Q is connected to aconnecting point between the resistor R1 and the constant voltage diodeZD. In the LED package, four LED chips are, as described above,connected in series, and hence, a series circuit of the transistor Q andthe resistor R2 may be constructed for each of the LED packages and thenconnected in parallel with each other.

A constant current circuit is constituted by the circuit mentionedabove, and a current supplied from the commercial power supply AC isconverted to a DC current, and such DC current flows, as constantcurrent IF, in the series circuit of the LED chips LED, the transistor Qand the resistor R2. More specifically, a base voltage VB of thetransistor Q is kept constant by the constant voltage diode ZD so thatcurrent IC flowing into a collector of the transistor Q is keptconstant, and as a result, the current IF flowing in the LED chip ismade constant.

According to the present embodiment described above, the light-emittingelements 3 are arranged in the central portion of the component mountingsurface of the substrate 2, and the lighting circuit components 4 andthe connector 5 for connecting with power supply are arranged around thelight-emitting elements 3. Accordingly, the light LH radiated from theside surface of the light-emitting elements 3, i.e., the LED packages,can be effectively used, making excellent light distribution and alsooptimizing light distribution. That is, when the light-emitting elements3, the lighting circuit components 4 and the connector 5 for connectingwith power supply are arranged in a mixed manner, particularly, thelight LH radiated from the side surface of the LED package isinterrupted by the lighting circuit components 4 and the like, thuslowering light extraction factor of the radiant light, not allowingeffective use of the radiant light, lowering the lighting efficiency andadversely affecting the optimization of light distribution.

According to the present embodiment, the lowering of light extractionfactor of the radiant light by the lighting circuit components 4 and thelike is reduced, and hence, the light LH radiated from the side surfacecan be effectively used. For example, when a reflector is used, theradiant light LH may be radiated in a direction of a surface to beirradiated. In addition, the light-emitting elements 3, the lightingcircuit components 4 and the connector 5 for connecting with powersupply are arranged in a concentrated manner, and as a result, thewiring pattern of the substrate 2 is shortened and simplified.

Further, since the light-emitting elements 3 as the heat sources are notarranged at the central portion of the substrate 2, and a rear surfaceside is formed as a flat heat dissipating surface, when the heatdissipating surface is in contact with another heat dissipating member,the heat is effectively transmitted from the central portion of thesubstrate 2 to the rear surface side, thereby easily realizing aconfiguration improving the heat dissipation effects.

Furthermore, since a modular structure including the connector 5 forconnecting with power supply is achieved, a lighting apparatus can beprovided merely by incorporating the substrate module 1 in the apparatusbody and then connecting a commercial power supply to the connector 5.Thus, the light-emitting module 1 can be handled as a single common parthaving a wide applicable field. Furthermore, since the connector 5 isarranged so that the connection opening 5 a thereof is disposed close tothe outer peripheral edge of the substrate 2, the connection with apower line of a commercial power supply is readily made, and inaddition, since the white resist is printed on the mounting surface ofthe substrate 2, the excellent reflection efficiency can be provided.

Hereunder, a first embodiment of a lighting apparatus according to thepresent invention will be described with reference to FIG. 4.

FIG. 4 is an illustration showing schematic structure of a lightingapparatus. Referring to FIG. 4, a lighting apparatus 10 is, for example,a downlight and includes an apparatus body 11. Included in the apparatusbody 11 are a heat dissipating member 12 made of metal having heatdissipating fins, a light-emitting module 1 attached to the heatdissipating member 12, and a reflector 13. The light-emitting module 1is screwed to the heat dissipating member 12 so that a heat dissipatingsurface on a rear surface side 2 b of the substrate 2 is closelyattached to the heat dissipating member 12 through a silicon rubbersheet. Needless to say, this mounting of the light-emitting module 1 maybe made by means of bonding or the like, instead of screw fastening. Thereflector 13 has a shape of a bowl having a gently curved surface andhas an opening in its upper and lower ends. The upper end constitutes amounting opening 13 a, and the lower end constitutes a radiating opening13 b.

As for the positional relationship with the light-emitting module 1,i.e., the positional relationship with the component mounting surface ofthe substrate 2, the mounting opening 13 a of the reflector 13 isdisposed so as to separate the light-emitting elements 3 from thelighting circuit components 4 and the connector 5 for connecting withpower supply, arranged around the light-emitting elements 3. That is,the light-emitting elements 3 are divided from the lighting circuitcomponents 4 and the like by the reflector 13. Thus, the light radiatedfrom the light-emitting elements 3 is not interrupted by the lightingcircuit components 4 and the like and is reflected on the reflector 13and radiated downward. Further, since the lighting circuit components 4are not seen from the front surface side of the reflector 13, the outerappearance of the lighting apparatus 10 can be also improved.

According to the present embodiment, there is provided the lightingapparatus 10 capable of achieving more effective distribution of theradiant light from the light-emitting elements 3 in addition to theabove described effects of the light-emitting module 1.

The lighting apparatus is not limited to the above embodiment, and thelight-emitting module 1 may be mounted in a light source having a cap,or may be incorporated in lighting equipment used indoors or outdoors.

A second embodiment of the lighting apparatus according to the presentinvention will be described hereunder with reference to FIG. 5.

In this embodiment, a downlight type lighting apparatus, using anelectric-bulb shaped LED lamp as the light source, is shown.

Referring to FIG. 5, the lighting apparatus mounted on a ceiling surfaceincludes an apparatus body 10 and a light source 20 having a shape of anelectric bulb, mounted to the apparatus body 10.

The light source 20 includes: a light-emitting module 1 according to thefirst embodiment having the light-emitting elements 3 mounted thereon; amain body 21 thermally coupled to the light-emitting module 1 andworking as a heat dissipating member; and a glove 22 attached, throughan insulating member, to the main body 21 so as to cover, for example, acap of E26 and the light-emitting module 1.

The apparatus body 10 includes a. case 15 made of metal and having abox-shaped structure having an opening in formed in a lower surfacethereof, and a reflector 16 made of metal fitted into the opening of thecase 15. The reflector 16 is formed by a metal plate of aluminum or thelike, for example, and a decorative frame 16 a is formed to a peripheralportion of the lower surface of the reflector 16. A socket 17, in whichthe cap of the light source 20 is screwed, is arranged at the center ofan upper surface plate of the reflector 16. The socket 17 is attached tothe case 15 via a support plate 18 secured to the inner side of the case15.

According to the present embodiment, there is provided a lightingapparatus with an LED lamp in the shape of an electric bulb, whichachieves the effects mentioned above with reference to thelight-emitting module 1.

A third embodiment of the lighting apparatus according to the presentinvention will be described hereunder with reference to FIG. 6. The likereference numerals are applied to portions or elements corresponding tothose of the second embodiment, and repeated explanation thereof isomitted herein.

In this embodiment, there is provided a lighting apparatus illustratedas a downlight, using a thin LED lamp, as a light source 20, havingthickness smaller in a height direction of height. The light-emittingmodule 1 of the first embodiment is mounted in the light source 20 in asimilar manner, and a main body 21 functioning as a heat dissipatingmember is thermally coupled to the light-emitting module 1. A cap isprovided with a connecting pin 25 formed into GX53-shape. A socket 17 ismounted to a case 15, and connecting pins 25 for the cap areelectrically and mechanically connected to the socket 17.

According to the present embodiment described above, there is provided alighting apparatus with a thin-type LED lamp capable of achieving theeffects of the light-emitting module 1.

A modification of the light-emitting module according to the firstembodiment will be described hereunder with reference to FIG. 7. FIG. 7is a plan view illustrating a light-emitting module. The like referencenumerals are added to portions or elements corresponding to those of thefirst embodiment, and repeated explanation thereof is omitted herein.

Lighting circuit components 4 are mounted on a component mountingsurface of a substrate 2 in a manner concentrated in the central portionthereof. The lighting circuit components 4 include a fuse F, a capacitorC, a rectifier REC, a constant voltage diode ZD, resistors R1 and R2,and a transistor Q.

On the other hand, the light-emitting elements 3 are mounted around thelighting circuit components 4 in a pattern spaced with a predeterminedinterval from each other. In a connector 5 for power supply connectionis arranged so that a connection opening 5 a thereof is disposed closeto the outer peripheral edge of the substrate 2. In consideration of theconnection with a power line, although it is preferred that theconnector 5 for the power supply connection is disposed to a portion inthe vicinity of the outer periphery of the substrate 2, the connectormay be arranged at the central portion together with the lightingcircuit component 4.

In this modified embodiment, the positional arrangement of thelight-emitting elements 3 and the lighting circuit components 4 of thefirst embodiment are reversed, and since the mounting interval of thelight-emitting elements 3 is greater than that of the first embodiment,light LH radiated from the side surface of the LED package can beeffectively utilized as like as in the first embodiment, and inaddition, by increasing the interval between the light-emitting elements3, 3 . . . , the heat of the light-emitting elements 3 can betransmitted and dissipated to the rear side of the substrate 2 byeffectively utilizing the entire structure of the substrate 2.

Hereunder, there will be explained an embodiment, with reference toFIGS. 8 to 13, in which the interval between the plurality oflight-emitting elements 3, 3, . . . mounted on the substrate 2, anddegree of luminance irregularity and variation in light-emittingefficiency both dependent on the interval, have been studied withrespect to the light-emitting module 1 according to the firstembodiment.

Referring to FIG. 8, the light-emitting elements 3 constitute asurface-mounted LED package and are composed of a main body 3 a, an LEDchip mounted on the main body 3 a, and a translucent resin 3 b forsealing the LED chip, and this translucent resin 3 b functions as alight-emitting unit L.

The light-emitting unit L is, as illustrated in FIG. 8( a), formed so asto have a substantially quadrate shape which is 2.8 mm on a side (W) andabout 4 mm on a diagonal (a). As illustrated in FIG. 8( b), thelight-emitting element 3 mounted on the substrate 2 is 1.5 mm in height(b) from the mounting surface of the substrate 2 to an upper surface ofthe light-emitting unit L and is 0.7 mm in height (h) of thelight-emitting unit L.

FIG. 9 is a graph showing a directional characteristics or pattern ofthe light-emitting elements 3. The light-emitting element 3 has amaximum illuminance in a direction perpendicular to the upper surface,i.e., at a radiation angle of 0.degree., and as for a direction of theside surface, has a illuminance 40 percent or greater relative to themaximum illuminance at a radiation angle of 80.degree. and a illuminance50 percent or greater relative to the maximum illuminance at a radiationangle of 70.degree., thus radiating a given amount of light in adirection along the component mounting surface.

The light-emitting elements 3 having such configuration andcharacteristics were arranged in a pattern spaced at a predeterminedinterval from each other as shown in FIG. 10. Thereafter, luminanceirregularity and light-emitting efficiency were measured and evaluatedby changing the interval.

Here, it was supposed, as illustrated in FIG. 10, that character cdenotes a minimum distance between the light-emitting units L1 and L2,and character a denotes a width of the light-emitting units L1 and L2 ona line of the minimum distance c. The method of evaluating luminanceirregularity was made such that the light-emitting module 1 was made toglow at a height of 2.5 m from the floor surface to illuminate the floorsurface, and the state of illumination on the floor was observed toperform visual evaluation. This visual evaluation was, as illustrated inFIG. 11, performed by observing illuminance distribution on the floor.Further, FIG. 11 is a figure that schematically illustrates, with thesolid line, a boundary line at which illuminance difference appears,more specifically, an image of light-emitting pattern (mounting patternimage of the light-emitting elements 3) of the light-emitting elements3. Thus, the evaluation is ranked as follows. In pattern A, luminanceirregularity is not noticed at all, in pattern B, luminance irregularityis hardly noticed, in pattern C, luminance irregularity is noticed, andin pattern D, luminance irregularity is clearly observed. Roughlyspeaking, when the interval between the light-emitting units L of thelight-emitting elements 3 is small, the luminance irregularity may beeliminated, the adjacent light-emitting elements 3 interrupt the radiantlight, thus lowering light emission efficiency. On the other hand, whenthe interval between the light-emitting units L is wide, the lightemission efficiency becomes high, but the luminance irregularity tendsto occur.

As a result of the above evaluation and measurement, evaluation andmeasurement values were obtained as shown in FIG. 12. Referring to FIG.12, the abscissa indicates interval c between the light-emitting units Lof the light-emitting elements 3, and the ordinate indicates luminanceirregularity evaluation and measurement values of light emissionefficiency. Further, it was found that as the interval c exceeded 4 mm,the luminance irregularity gradually lowered and deteriorated and thatas the interval c increased, the light emission efficiency raised.However, when the interval c exceeded 8 mm, it was found that the lightemission efficiency saturated.

In consideration of the above results, it was confirmed that thepermissible range of luminance irregularity lied around rank C, and inconsideration of the light emission efficiency, it was also confirmedthat the interval c between the light-emitting elements 3 was preferablygreater than b and smaller than 4a (b≦c≦4a). Furthermore, it wasresulted that the optimum range in the above range for further enhancingluminance irregularity evaluation and improving the light emissionefficiency was a range of 2b.ltoreq.c.ltoreq.3a. Still furthermore, inorder to suppress effect due to heat generation between thelight-emitting elements 3, an optimum arrangement pattern was a<c. Inthe case of a<c, the temperature of the light-emitting elements 3 duringglowing could be suppressed from rising. A lower limit value of theabove interval c may also be represented by height h of thelight-emitting unit L, and when this height h is used, a relationship ofapproximately 2h<c, preferably, 4h.ltoreq.c will be obtained.

In the above, the present embodiment, was described with reference to asan example by considering the relationship between the light-emittingunits L1 and L2 of the light-emitting elements 3 illustrated in FIG. 10.However, for example, the dimensional relationship of the interval c inthe light-emitting units L2 and L3 is similar to that of thelight-emitting units L1 and L2. The dimensions, the directionalcharacteristics and the like of the light-emitting elements 3 are notlimited to the specific dimensions and characteristics described withreference to this embodiment. The mounting pattern of the light-emittingelements 3 is not limited to the pattern in which light-emittingelements 3 are, as illustrated in FIG. 10, arranged on thecircumference, and it may be sufficient that minimum distance c betweenthe light-emitting elements 3 falls into the above prescribed range. Forexample, the light-emitting elements 3 may be arranged in a matrixpattern.

A light-emitting element 30 illustrated in FIG. 13 may also be used asthe light-emitting element. This light-emitting element 30 is asurface-mounted LED package, and this LED package is composed of a mainbody 30 a formed of ceramics, a reflector 30 d arranged on the main body30 a, an LED chip 30 c mounted in a recess defined by the main body 30 aand the reflector 30 d, and a silicon resin 30 e for sealing the LEDchip 30 c. This silicon resin 30 e functions as the light-emitting unitL, and light is radiated from the light-emitting unit L in a radialpattern which is similar, as a whole, to the directional characteristicsillustrated in FIG. 9, including an upper surface direction and adirection along the component mounting surface.

INDUSTRIAL APPLICABILITY

According to the present invention, there is provided a light-emittingmodule having a wide applicable scope and improving and optimizing thedistribution of light radiated from the light-emitting element. Inaddition, the heat dissipation effects can be raised, and an effect ofshortening and simplifying a wiring pattern on a substrate can be alsoachieved.

1. A lamp device comprising: a lighting circuit including at least a rectifier; a light emitting diode; and a substrate, wherein the lighting circuit and the light emitting diode are both mounted on the substrate.
 2. The lamp device of claim 1, further including a connector configured to connect to a power supply and to provide power to the lighting circuit and the light emitting diode, wherein the connector is mounted to the substrate.
 3. The lamp device of claim 2, wherein the connector and the lighting circuit are located closer to a peripheral edge of the substrate than the light emitting diode.
 4. The lamp device of claim 1, wherein the lighting circuit and the light emitting diode are mounted on a same surface of the substrate. 